1. Geological Survey Map, Sheet 6, Old Series.
2. Ordnance Survey Map. Sheet 288, New Series.
3. Flint Drift of S.-E. England;Murchison;Quart, Journ. Geol. Soc.,1851
4. Geology of the Weald;Topley;Mem. Geol. Surv.,1875
5. Ightham;Bennett;Homeland Assoc.,1908